I'm not prone to raining on anyone's parade, least of all to the man who shoots down pictures (and most eloquently, at that), but David Niven appears most prominently and effectively in Powell/Pressburger's "Matter of Life and Death"(#181), and not-so prominently as an extra (according to IMDB) in "Mutiny on the Bounty" (#862).
Whenever I am in cell phone replacement mode I do research at Howard Forums. Although I didn't check for your question specifically, they are a great source of information.